Sodium cyanate, a chemotherapeutic agent for Sickle Cell disease, inhibits irreversibility of the sickling of erythrocytes from patients with this disease by reacting specifically with the NH2-terminal valine of the hemoglobin molecule without significantly destroying erythrocyte metabolism or function. It has been suggested that sodium cyanate may elicit neuropathology in pigtail monkeys, Macaca nemastrina. The outcome of this study will provide information for development of further clinical studies for use in humans suffering from Sickle Cell disease.